Plasticized polyvinyl chloride (PVC) is widely used in medical applications such as IV-bags, blood bags, connectors, and tubing. Drawbacks to the use of plasticized PVC include the undesired environmental impact related to the release of dioxins when PVC is incinerated in an uncontrolled manner. Additionally, migration of plasticizers, so-called “oestrogen mimics”, from plasticized PVC into the human body may have a negative health effect. These two major disadvantages are the driving force behind the development of PVC alternatives.
WO 2014/002984 A1 discloses hydrogenated block copolymer pellets which are free from blocking with each other and formed into a molded body that has excellent transparency, flexibility, bleed-out properties and low combustion ash content. The hydrogenated block copolymer pellets contain 100 parts by mass of a pellet molded body that is formed of a hydrogenated block copolymer (A) and 0.01-1.5 parts by mass of flour that is formed of a polyethylene powder (B). The hydrogenated block copolymer (A) has at least one polymer block (a) that is mainly composed of a vinyl aromatic monomer unit and at least one polymer block (b) that is mainly composed of a conjugated diene monomer unit and has a total of the 1,2-bond content and the 3,4-bond content of 40-90% before hydrogenation. The hydrogenated block copolymer (A) has a hardness of 30-67; the content of the polymer block (a) in the hydrogenated block copolymer (A) is 5-30% by mass; and the polyethylene powder (B) has a number average molecular weight of 15,000 or less, an average particle diameter of 1-15 μm and a repose angle of 45-70°.
EP 2407512 A1 discloses a tube which has good transparency, flexibility, and solvent adhesion, and also has excellent clamp resistance, anti-conglutination property, and kink resistance, and a medical device using the tube. Specifically provided are a tube produced by forming a resin composition into a tube shape, which contains a styrene-based thermoplastic elastomer (a) and a polypropylene-based resin (b) and does not contain a softening agent, in which: the elastomer (a) is a product prepared by hydrogenating a block copolymer including at least a polymer block (A) formed of an aromatic vinyl compound and a polymer block (B) formed of isoprene and/or 1,3-butadiene; the content of the polymer block (A) is 5 to 40 mass % before hydrogenation, the polymer block (B) has a hydrogenation ratio of 70% or more, and the polymer block (B) includes a 1,2-bond and a 3,4-bond at a content of 30 to 85 mol percent; the mass ratio of the styrene-based thermoplastic elastomer (a) to the polypropylene-based resin (b) [(a)/(b)] is 90/10 to 40/60; and the tube has a ratio of a diffraction peak intensity [I(14)] at a scattering angle of 14° to a diffraction peak intensity [I(15)] at a scattering angle of 15° [I(14)/I(15)] of 1.4 or more in X-ray diffraction, and a medical device including the tube.
U.S. Pat. No. 6,846,535 discloses a kink resistant medical tube manufactured from a polymer composition comprising: a) a random polypropylene copolymer; and b) a block copolymer comprising at least two vinyl aromatic polymer blocks and at least one hydrogenated conjugated diene polymer block, wherein the hydrogenated conjugated diene polymer block has a vinyl content before hydrogenation of at least 50%.
U.S. Pat. No. 7,439,301 discloses an elastomeric hydrogenated block copolymer capable of being directly extruded or molded with a minimum of additives and having both high elasticity and low permanent set. The hydrogenated block copolymers have high melt flows allowing for ease in processing the hydrogenation block copolymers in melt processes such as extrusion and molding.
Thus, there exists a need for alternatives to PVC based compositions.